A possible role for leptin in normo- or hypoparathyroid uremic bone in postmenopausal dialysis women.

Leptin has been proposed to be a key molecule involved in energy regulation. Based on the generally acknowledged concept that a heavier person has a higher bone density, leptin is thought to be potentially involved in bone metabolism. Serum leptin, various bone markers, and bone mineral density (BMD) were studied in 51 dialysis patients (26 men and 25 women). The serum concentrations of leptin in dialysis patients ranged from 0.7 to 10.4 ng/ml (mean 3.2 +/- 2.1 ng/ml) for males and from 1.4 to 44.6 ng/ml (mean 11.8 +/- 10.4 ng/ml) for females. There was a good correlation between the body mass index (BMI) and leptin concentration in both male and female patients (P < 0.05). Serum leptin levels also correlated well with the age-adjusted z-score for BMD (P < 0.02) and were inversely correlated with levels of the carboxy-terminal propeptide of type I procollagen (P < 0.05) in females patients, but not in male patients. In conclusion, these results suggest an actual contribution of serum leptin in maintaining bone density in postmenopausal female dialysis patients.